Gu Tao actually only found out recently that the dust python can reach a maximum length of two thousand kilometers. They linger at the bottom of the sea, and compared to them, the size of the great octopus Kraken is hardly a mouthful. However, it is said that the largest being is not the dust python but the legendary Kun, which is so large that... the entire Mountain and Sea Realm is transformed from its body. Its will turned into the Mountain and Sea Realm's barriers, its physical body into the sun, moon and stars, mountains, rivers and oceans of the Mountain and Sea Realm, which is why the Mountain and Sea Realm can be regarded as an independent parallel world while the Thirty-Three Heavens cannot.
The Thirty-Three Heavens, by nature, is like Kunlun and not independent of this world, merely situated in another space, but the Mountain and Sea Realm is a complete world with its own rules.